In climates with a cold season, it is conventional to equip automobile engines with a block heater for enabling easier starting at cold temperatures. The block heaters typically have a lead power cord which extends out of the hood of the car or hangs through the radiator grill. Usually an automobile owner uses an extension cord to extend between the lead power cord and a power source. The power source is usually an electrical outlet at home or at a parking lot.
Extension power cords are usually unattended overnight or even for days at a time. Further, they are nondescript, easy to conceal, may be stolen in seconds and are not damaged by theft.
There is therefore demonstrated a need for a simple, inexpensive means for increasing the difficulty of taking a cord and thereby reduce the incidence of extension cord theft.